CalculationTime

Sunrise Star Map

Date+ location+ altitude -0.833 deg= sunrise
KnownDate + placeFindSunriseAltitude-0.833 degAzimuthTrue bearingSkyPre-dawnLimitLevel horizon
CalculationTime

Sunrise Star Map

A pre-dawn sky calculator aligned to true sunrise azimuth for the selected place and date, framed in the shared CalculationTime calculator and clock system.

Inputs, result, proof and time.

Use the instrument above, then check the calculation record, assumptions and related tools below.

Direct answer

Sunrise Star Map in one sentence

The Sunrise Star Map calculates sunrise time, true sunrise azimuth and the one-hour-before-dawn star field for a selected place and date.

How to use this calculator

  1. Choose the city or coordinates and set the observation date.
  2. Read the calculated sunrise time and true azimuth before using the pre-dawn star map.
  3. Print the dawn sky worksheet when you need the place, date, horizon assumptions and map context together.

Default result preview

Default solved state: selected place/date sunrise azimuth and pre-dawn star field

The client tool renders a solved dawn map immediately so readers and crawlers do not encounter a blank calculator.

How to prompt AI with this result

Copy this prompt with the visible result when you want a second-pass explanation, comparison or next-step checklist.

Use this CalculationTime result from Sunrise Star Map.
Direct answer: The Sunrise Star Map calculates sunrise time, true sunrise azimuth and the one-hour-before-dawn star field for a selected place and date.
Default result: Default solved state: selected place/date sunrise azimuth and pre-dawn star field
Method/formula: Sunrise uses solar altitude -0.833 degrees; the star map projects visible stars using local sidereal time for the selected latitude, longitude and date.
Source boundary: Educational sunrise and star-projection guide. The page uses a standard sunrise-altitude convention and Astronomy Engine context, but local terrain, weather and official almanac checks remain outside the calculation.
Explain the result, list the assumptions that matter, and suggest the next practical check without changing the original calculation.

Authority & freshness

Who checked this calculator?

Page structure checked: 2026-09-26. The sunrise altitude and horizon assumptions remain visible beside the tool.

Last verified:

Published by CalculationTime

CalculationTime publishes this tool with visible method notes, limits, related next steps and printable records so the result can be checked instead of treated as a black box.

Machine-readable formula

Sunrise uses solar altitude -0.833 degrees; the star map projects visible stars using local sidereal time for the selected latitude, longitude and date.The formula or method statement is rendered as text so crawlers and readers can extract the variables.

Source basis

2 source references support this page.

Boundary: Educational sunrise and star-projection guide. The page uses a standard sunrise-altitude convention and Astronomy Engine context, but local terrain, weather and official almanac checks remain outside the calculation.

NASA Moon phase basis | Astronomy Engine

Fallback visual

Sunrise Star Map without the live visualizer

If the live star map cannot render, the page still describes the selected place/date inputs, sunrise altitude assumption, sunrise azimuth target and sidereal star-projection method.

Static fallback text

The fallback reading is: solve sunrise near -0.833 degrees solar altitude, subtract one hour for the pre-dawn view, then project visible stars above a level mathematical horizon around the true sunrise azimuth.

What crawlers can extract

  • Input: observation date and anchor location.
  • Method: sunrise altitude correction plus local sidereal time.
  • Boundary: terrain, buildings, haze and weather are not modelled.

Why this matters

The interactive visual is helpful, but the method must remain understandable when JavaScript, canvas, iframe loading or graphics acceleration are unavailable.

Parameters

Sunrise star maps rely on date, location and true horizon geometry.

60 min before sunrise
Geolocation
Latitude51.5072°N
Longitude0.1276°W
Syncing celestial catalog...

Live math canvas

Your numbers, formula and explanation together

The star map calculates sunrise time, true sunrise azimuth and the pre-dawn sky projection for the selected place and date.

Formula applied

The exact method behind this answer

CalculationTime keeps the method visible so the number can be checked instead of blindly trusted.

Sunrise is solved near solar altitude -0.833 degrees; the star map uses local sidereal time to project visible stars above the horizon.
  1. Apply the methodSunrise is solved near solar altitude -0.833 degrees; the star map uses local sidereal time to project visible stars above the horizon.Sunrise azimuth and star fieldThe selected place and date determine the sunrise point and visible pre-dawn stars.

Your live breakdown

Current calculator context

This page keeps the active calculator, default worked example and method beside the tool so the answer is not separated from its arithmetic.

Calculator
Sunrise Star Map
Computed dawn sky
Sunrise azimuth and star field
Current method
Sunrise is solved near solar altitude -0.833 degrees; the star map uses local sidereal time to project visible stars above the horizon.

Resulting answer

Sunrise azimuth and star field

The selected place and date determine the sunrise point and visible pre-dawn stars.

Calculator
Sunrise Star Map
Computed dawn sky
Sunrise azimuth and star field
Current method
Sunrise is solved near solar altitude -0.833 degrees; the star map uses local sidereal time to project visible stars above the horizon.

Assumptions used

What this answer assumes

These boundaries keep the calculation honest and make clear when a specialist rule set is needed.

  • Sunrise uses a standard -0.833 degree altitude correction for refraction and solar semi-diameter.
  • The horizon is treated as a level mathematical horizon.
  • The star projection depends on latitude, longitude, date and local sidereal time.
  • Buildings, hills, elevation, haze and weather are not modelled.

Master’s Tip

How to use the result well

Master’s Tip: use the map as a planning guide, then check local horizon obstructions and weather before expecting the sky to match perfectly.

Printable record

What belongs in the saved calculation

For a selected city and date, the page finds the sunrise time, subtracts one hour for the pre-dawn view, then centres the map on the true sunrise azimuth.

Calculator
Sunrise Star Map
Computed dawn sky
Sunrise azimuth and star field
Current method
Sunrise is solved near solar altitude -0.833 degrees; the star map uses local sidereal time to project visible stars above the horizon.

Embeddable calculator

Embed this calculator

Copy a clean iframe version with the required CalculationTime attribution link built in.

Methodology & Accuracy

Calculation method and limits

The page combines a standard sunrise altitude correction, Julian-date solar position arithmetic and local sidereal time to draw a practical pre-dawn sky view.

Mathematical assumptions

Sunrise is anchored to -0.833 degrees solar altitude, combining standard atmospheric refraction and the solar semi-diameter used for upper-limb sunrise estimates.

Sky projection

The map evaluates local sidereal time, projects visible stars above the horizon, and centres the view on the calculated sunrise azimuth.

Horizon limitations

Results assume a level mathematical horizon. Hills, buildings, elevation, weather and magnetic declination can change field observations.

Print room: dawn sky worksheet

Print the sunrise-time and star-map context so the selected place, date, azimuth and horizon assumptions stay together.

Source ownerSunrise altitude correction, local sidereal projection and CalculationTime star-map rendering.
Best usePlanning or teaching the pre-dawn sky above the true sunrise point.
BoundaryLevel-horizon model; buildings, terrain, elevation, haze and weather are outside the calculation.

Before using the worksheet, check the selected place/date, high-latitude boundary, mobile controls, labels and printed dawn sheet.